use of shrimp sludge as a soil amendment for tomatoes chad king, kevin fitzsimmons, dennis mcintosh...
TRANSCRIPT
Use of Shrimp Sludge as a Soil Amendment for Tomatoes
Chad King, Kevin Fitzsimmons, Dennis McIntosh
Environmental Research LabUniversity of Arizona
Purpose
• Determine feasibility of use of shrimp sludge from low salinity inland shrimp culture as a soil amendment.
• Apply sludge at disposal rates, not to meet plant requirements.
• Provide a use or disposal for a current waste product
• Reduce the potential for farm erosion, nutrient leaching/loss
Research Design• Collected and dried fresh sludge from a shrimp farm
in western Arizona, USA • Treatments of 5, 10 and 20% sludge application by
volume, 402, 805 and 1,610 g/plant• Mechanically mixed shrimp sludge and potting soil
mix (concrete sand, mulch, vermiculite)• Randomly transplanted and arranged 28 ‘Roma’
tomato starts in a greenhouse, one plant per pot• Each plant received 4 L of water daily, over four
applications by drip irrigation• Response measured in mass of tomatoes produced
Shrimp Sludge Characteristics
Sample Total N
% dry matter
Total PO4-P
% dry matter
Total K
% dry matter
NO3-N
g/g
Olsen P
g/g
Soluble K
g/g
EC
dS/m
1 0.13 0.10 0.23 1497.4 22.60 27.3
2 0.48 0.21 0.20 4.36 73.50 53.6 8.5
Total N, PO4-P and K show total plant macronutrients
NO3-N, Olsen P and soluble K show plant available nutrients
EC provides a measurement of soil salinity
Tomato Production
Treatment Tomato Mass (g/plant)
SEM
0% (Control) 39.2a 11.54
5%402 g/plant
65.1a 11.14
10%805 g/plant
141.1b 20.73
20%1,620 g/plant
113.6b 19.9
Different superscripts indicate a significant difference, p<0.05
Conclusions
• Applications of 10% and 20% increased plant production
• Suggests land application will benefit crop production while providing a disposal mechanism
• Large, field scale application experiment suggested to verify results
• Soil salinity must also be monitored, given high evaporation rates
• Sludge is highly variable, depending on pond management